"Late last night we started receiving reports from readers experiencing problems with Windows Genuine Advantage authentication. Users of both Windows XP and Windows Vista were writing to say that they could not validate their installations using WGA, and one user even said that his installation was invalidated by the service. We contacted our sources at Microsoft, who told us off the record that the company is aware of a major WGA server outage affecting users across the globe. Microsoft is telling users who are affected that they should 'try again' later, with some support techs telling readers that Microsoft is aiming to have a fix in place by Tuesday, August 28th."